iio: core: drop devm_iio_trigger_unregister() API call

It's unused so far, so it can be removed. Also makes sense to remove it
to discourage weird uses of this call during review.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Documentation/driver-api/driver-model/devres.rst

@@ -291,7 +291,6 @@ IIO
   devm_iio_trigger_alloc()
   devm_iio_trigger_free()
   devm_iio_trigger_register()
-  devm_iio_trigger_unregister()
   devm_iio_channel_get()
   devm_iio_channel_release()
   devm_iio_channel_get_all()

Documentation/driver-api/iio/triggers.rst

@@ -6,7 +6,6 @@ Triggers
 * :c:func:`devm_iio_trigger_alloc` — Resource-managed iio_trigger_alloc
 * :c:func:`devm_iio_trigger_free` — Resource-managed iio_trigger_free
 * :c:func:`devm_iio_trigger_register` — Resource-managed iio_trigger_register
-* :c:func:`devm_iio_trigger_unregister` — Resource-managed
   iio_trigger_unregister
 * :c:func:`iio_trigger_validate_own_device` — Check if a trigger and IIO
   device belong to the same device

drivers/iio/industrialio-trigger.c

@@ -673,9 +673,6 @@ static void devm_iio_trigger_unreg(struct device *dev, void *res)
  * calls iio_trigger_register() internally. Refer to that function for more
  * information.
  *
- * If an iio_trigger registered with this function needs to be unregistered
- * separately, devm_iio_trigger_unregister() must be used.
- *
  * RETURNS:
  * 0 on success, negative error number on failure.
  */
@@ -701,24 +698,6 @@ int __devm_iio_trigger_register(struct device *dev,
 }
 EXPORT_SYMBOL_GPL(__devm_iio_trigger_register);
 
-/**
- * devm_iio_trigger_unregister - Resource-managed iio_trigger_unregister()
- * @dev:	device this iio_trigger belongs to
- * @trig_info:	the trigger associated with the device
- *
- * Unregister trigger registered with devm_iio_trigger_register().
- */
-void devm_iio_trigger_unregister(struct device *dev,
-				 struct iio_trigger *trig_info)
-{
-	int rc;
-
-	rc = devres_release(dev, devm_iio_trigger_unreg, devm_iio_trigger_match,
-			    trig_info);
-	WARN_ON(rc);
-}
-EXPORT_SYMBOL_GPL(devm_iio_trigger_unregister);
-
 bool iio_trigger_using_own(struct iio_dev *indio_dev)
 {
 	return indio_dev->trig->attached_own_device;

include/linux/iio/trigger.h

@@ -141,9 +141,6 @@ int __devm_iio_trigger_register(struct device *dev,
  **/
 void iio_trigger_unregister(struct iio_trigger *trig_info);
 
-void devm_iio_trigger_unregister(struct device *dev,
-				 struct iio_trigger *trig_info);
-
 /**
  * iio_trigger_set_immutable() - set an immutable trigger on destination
  *